Miniature solid state microwave source



Dec. 16, 1969 v. BOXER MINIATURE SOLID STATE MICROWAVE 'SOURCE Filed Jan. 10, 1968 INVENTOR VICTOR BOXER.

ATTORNEYS.

United States Patent 3 484 661 MINIATURE SOLID s'rArit MICROWAVE SOURCE Victor Boxer, Belrnar, N.J., assignor to the United States of America as represented by the Secretary of the Army Filed Jan. 10, 1968, Ser. No. 696,875 Int. Cl. H011 11/00, 15/00 U.S. Cl. 317-235 4 Claims ABSTRACT OF THE DISCLOSURE The invention descibed herein may be manufactured, used, and licensed by or for the Government for governmental purposes without the payment to me of any royalty thereon.

BACKGROUND OF THE INVENTION This invention relates to solid state oscillators and more particularly to a miniature solid state microwave oscillator utilizing coaxial type or planar stacked transistors.

With the advent of microwave miniature circuitry it is desirable to provide microwave sources of reasonably small dimensions and lightweight and yet be capable of providing ample output power.

SUMMARY OF THE INVENTION It is an object of the present invention to provide an improved miniature solid state microwave source.

In brief, there is provided a miniaturized solid state microwave power source which includes a coaxial or planar stacked type of transistor having axially aligned collector, base and emitter electrodes in that order, with the base electrode being provided with a disc seal. Included further is a metallic disc affixed or clamped to the base electrode and a spring-fingered metallic contact for engaging the collector electrode. Also included is a multi-finned brass sink, preferably two fins, affixed to the spring-fingered contact, and a split brass ring intermediate the base electrode and the two-finned brass sink and insulatably spaced from both the two-finned brass sink and the base electrode. The split brass ring is also insulatably spaced from the collector electrode.

BRIEF DESCRIPTION OF THE DRAWING For a better understanding of the invention, together with other and further objects thereof, reference is had to the following description taken in connection with the accompanying drawing in which:

FIG. 1 is an exploded view of the present invention; and

FIG. 2 illustrates the schematic equivalent of the microwave source.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now to FIG. 1 of the drawing, at there is shown a coaxial type transistor having a base electrode 12 with a metallic disc seal 13 aflixed and sealed thereon, an emitter electrode 14 and a collector 16, arranged 'ice along the axis 13. Affixed to base disc seal 13 and in contact therewith is a metallic cross-shaped element 20 which is provided with a central aperture 22 through which the emitter electrode 14 extends. The size of the aperture 22 is such that there is a circumferential air gap between axial emitter electrode 14 and element 20. Collector electrode 16 engages and is mounted in a spring-fingered beryllium contact 24 to which is soldered a pair of airspaced brass washers 26. Intermediate base electrode 12 and brass washers 26, there is positioned a split brass ring 28 which is spaced from cross-shaped element 20 and brass washers 26 by means of Teflon spacers 30 which engage appropriate aligned holes to maintain the brass ring in the spaced position. The center bore of brass ring 28 is dimensioned so that it is clear of the axial collector electrode 16. For a common collector configuration, the beryllium fingered contacts 24 and brass Washers 26 are at ground potential and may be fastened to a suitable container 32, for added sink surface. When used in common base circuit, the cross-shaped element 20 is grounded and the brass washers 26 become part of the collector tank circuitry. In either case, the split brass ring 28 functions as an output pick-up loop to which an ou put coaxial cable is connected. In the grounded collector configuration, the cross-shaped element 20 also functions as an inductor. The bias network system, shown at 34, is mounted above the cross-shaped element 20. It has been found that for higher frequency operation, the arm of cross-shaped element 20 may be connected by a strap as indicated by the dashed line in FIG. 1 of the drawing.

FIG. 2 illustrates the equivalent electrical circuit of the arrangement shown in FIG. 1. Like members refer to like elements.

While there has been described what is at present considered to be the preferred embodiment of this invention, it will be obvious to those skilled in the art that various changes and modifications may be made therein without departing from the invention.

What is claimed is:

1. A miniaturized solid state microwave source comprising a coaxial type transistor having axially aligned collector, base, and emitter electrodes in that order,

a metallic disc afiixed to said base electrode,

a spring fingered metallic contact for engaging said collector electrode,

a sink for said collector electrode aflixed to said spring fingered contact,

and a split metallic ring intermediate said base electrode and said sink and insulatably spaced therefrom.

2. The microwave source in accordance with claim 1 wherein said disc is a cross-shaped member.

3. The microwave source in accordance with claim 1 wherein said sink comprises a pair of air-spaced brass washers.

4. The microwave source in accordance with claim 3 wherein said disc is a cross-shaped member having a central aperture through which said emitter electrode extends.

References Cited UNITED STATES PATENTS JERRY D. CRAIG, Primary Examiner US. Cl. X.R. 333-98 

